Transmission control system



y 1953 A. WINTHER ET AL 2,638,793

TRANSMISSION CONTROL SYSTEM Filed March 29, 1951 4 Sheets-Sheet 1 IN VEN TOR.

ANTHONY WINTHER MAR m P. WlNTHER ATTORNEYS y 19, 9 A. WINTHER ET AL 2,638,793

TRANSMISSION CONTROL SYSTEM Filed March 29, 1951 4 SheeEs-Sheet 2 ZELE.. 3

INVENTOR. ANTHONY Wm'rHER MARTIN P. WmTHER BY ATTORNEYs May 19, 1953 A. WINTHER ET AL 2,638,793

TRANSMISSION CONTROL SYSTEM Filed March 29, 1951 4 Sheets-Sheet 3 I; E 'INVENTOR;

ANTHONY WIMTHER MAR'HN F? WmTHER ATTORNEYS y 9, 1953 A. WINTHER ET AL 2,638,793

TRANSMISSION CONTROL SYSTEM Filed March 29, 1951 4 sheets-sheet 4 'LQI. 204 /l7.

2- 1 [98 I18 YLG g: 178 Q14 za4 nc 255 I47. 154 me,

25g 250 7% o i 20c 24'; 170

I I E E INVENTOR.

ANTHONY WHJTHER MAR'rm P. WINTHER BY ATTORNEYS Patented May 19, 1953 UNITED STATES PATENT OFFICE v 2,638,793 TRANSMISSION CONTROL SYSTEM Anthony Whither, Kenosha, Wis., and Martin I. Winther, Gates Mills, Ohio, assignors, by mesne assignments, to Eaton Manufacturing Com pany, Cleveland, Ohio, a corporation of Ohio Application March '29-, 1951, Serial No. 218,106

16 Claims. (Cl. 74'472) This invention relates to transmissions an more particularly to a control system therefor and constitutes a continuation-in-part of application Ser. No. 206,643 filed January 18, 1951, and application Ser. No. 86,201 filed April 8, 1949. now Patent No. 2,549,738.

Broadly the invention comprehends the provision of a governor controlled transmission control system for step-by-step type transmissions including therein an accelerator control for starting gear operation.

Among the objects of the invention are to provide a control system for step-by-step type transmissions that is simple and effective in operation; that is adaptable to vehicles for the automatic controlled gear speed operation thereof; that is electrical power supplied; that operates to effectatgear speed change corresponding to vehicle speeds; that utilizes a governor operable to cause a gear shift through the full speed range of vehicle forward operation; that provides for controlled acceleration of the vehicle, to which applied, when the vehicle is in starting gear; that provides for a five speed forward control of operation-in smooth ladder staging steps one totanother; and that provides for overlap in control of gear change effecting a smooth changeover from one gear speed to another gear speed in either upstaging or downstaging of transmission operation.

other objects and advantages of the invention will appear from the following description taken in connection with the drawings forming a Dart of the specification; and in which:

Fig. 1 is a schematic-layout of a control system I spending parts throughout the several views of the drawings.

This control system was devised primarily for use in the effective automatic control of the transmission disclosed by co pending application Ser. No. 86,201 whereby a smooth staging of operation is attained from first through fifth forward gear speed under the control of a speed governor driven from the propeller or like output I shaft of an engine driven vehicle or the like. In addition to the normal staging of gear speed change, a modulated acceleration controller starting gear speed is provided. The control system comprises basically an electrical power supplied system utilizing a propeller shaft driven governor as the gear staging control center whereby a specific combination or a multiple oi different ratio gear sets and a pair of electron magnetic clutches can be synchronized I61 the, proper effective and smooth operational" the transmission. The gear sets are adapted electrical control thereof to be actuated by any suitable power source such as air pressure, vac: uum or electric depending upon which ismost appropriate.

The acceleration control includes a variable resistance mechanism adapted to be connected in o a control circuit under the control of switches actuated by the accelerator pedal permitting of the operation of the variable resistance mechanism under the influence of engine vacuum for a modulated operational control of the starting sear clutch upon initial depression of the an! celerator pedal and whereby upon full depression of the pedal the variable resistance mechani m is by passed. This acceleration contra-1 is preferably restricted to the starting gear although it, might also be applied to the second gear stage. T 7 Referringto the drawings for more specific oletails of the invention It represents generally a control system Fig. 1 for a step-by-step typo transmission [2, Figs. 2 through 6. a The control system In is supplied current from an electrical source or" power such as :a battery I4 and includes a circuit l6 controlled as by a vs:- hicle engine ignition switch [8. l L

The circuit [6 includes a pair of major current conductors and 22, and brancheonductors 24 and 26.

Conductor 20 is adapted to supply current by: way of pigtail 28, fastened to a lever of apropeller shaft driven governor 32, to a series otspaced substantially arcuately arranged current conducting switch segments or contacts 34, 35. 38; 40 and 42.

Switch contact 34 is connected in a circuit]! including major and branch conductors 45, 48 and 50 respectively connected to contact terminal 52 of switch 54, coil 56 of a solenoid 58", and corp tact terminal 60 of switch 62. Swit h contact 36 is connected in a circuit 6-4 including conductor 66 temunatins in a contact terminal 68 of a switch 10 and a branchoom ductor I2 connected to a coil '14 of a.- solenoid 16.: Switch contacts 38, 40 and 42 are connected respectively by way of conductors 18, and 81 to the coils 34, as and as or solenoids 92 and 94. y

Conductor 24 terminates in spaced contact 3 terminals 96 and 98 forming apart of the respective switches 54 and and conductor 26 terminates in contact terminal I00 forming a part of switch 62.

An accelerator control circuit I02 interposed in conductor 22 includes a conductor I04 connected to one section A of conductor 22 terminating at opposite ends in contact terminals I06 and I08 respectively with a carbon pile variable resistor IIO connected in the conductor 22 intermediate the terminals thereof. Another section A, of conductor 22 set apart from the section connected to conductor I04 terminates in a contact terminal I I2 arranged in spaced relation intermediate contact terminals I06, I08.

A switch H4, is interposed in section A, of conductor 22 and is adapted to control the operation of accelerator control circuit I02 whereby, through appropriate connection with the shifting mechanism for the transmission I2 to which control system I0 is applied, the switch is not engaged until the transmission is out of neutral. A switch H6 is arranged intermediate the sections A and A, of conductor 22 operably conneoted to the transmission shift mechanism for an actuation thereof to close conductor 22 and effect a direct flow of current therethrough bypassing circuit I02 when the transmission has been shifted out of first or starting gear operation.

If it is desired switch II 4 can be dispensed with wherein provision is had so that no connection is made between the power plant and transmission I2 driven thereby until a movement of the vehicle is desired as controlled by governor 32.

The carbon pile resistor H0 is controlled by the operation of a vacuum actuated diaphragm II8 forming part of a vacuum cylinder I having conduit connection with the manifold of an engine with which transmission I2 is to be associated.

An accelerator pedal I22 has a part I24 thereof adapted to effect controlled contacting engagement of the contact terminals I06, H2 and I08 with an initial contact being affected between contact terminal I06 and H2 and thence between I06 and H2 and II 2'and I08 for current flow therethrough.

The opposite end of section A of conductor 22, has acoil I26 of an electromagnetic clutch I28 forming a material element of transmission I2, controlled as by a switch I29. The switch- I29 includes a pair of spaced contact terminals I30 and I32 in section A, of conductor 22 adapted to be bridged by a switch element I34 forming part of an armature I36 of solenoid 14.

A branch conductor I38 is connected to section A, of conductor 22, intermediate connection of coil I26 and switch I29 thereof and connection with circuit I02. The conductor I38 similarly to section A, conductor 22 terminates in coil I40 (such as coil I26) of a second electromagnetic clutch I42 forming another essential element of transmission I2, controlled as by a switch I44. The switch I44 includes a pair of spaced contact terminals I46 and I48 in conductor I38 adapted to bebridged by a switch element I50 forming part of an armature of solenoid I52.

The solenoids 90, 92 and 94 include in addition to their respective coils 84, 86 and 88, armatures I54, I56 and I58 each terminating respectively in valve elements I60, I62 and I64. The valve elements are arranged in valve housings I66, I68 and I10 therefor for controlling the flow of air pressure, from a source not shown, to the pressure chambers of respective air cylinders I12, I14 and I16. The valve elements I60, I62, and I64 in addition to controlling the flow of air from the air pressure source to the cylinders also control the release of air pressure from the cylinders to the atmosphere.

The air cylinders I12, I14, I16 have respective resiliently loaded diaphragms I18, I80 and I82 therein opposing the air pressure delivered to the cylinder and operative to be moved to exhaust the air from the cylinders when the valve elements connect the pressure chamber of the cylinders to the atmosphere.

Shiftable rods I84, I86 and I88 are connected at one end to the respective diaphragms I18, I80 and I82 and terminate at their opposite ends in switch elements I90, I92, I94 forming a part of the respective switches 62, 10 and 54.

Pivotal levers I96, I98 and 200 have their one free end freely connected to the respective rods I84, I86 and I88 and their other ends associated with collars 202, 204 and 206 of internal splines 208, 2I0 and 2I2 for the shifting thereof as actuated by movement of the respective levers I96,

I98 and 200.

Transmission I2 of the step-by-step type adapted to be controlled by electrical control system includes a power input shaft 2I4 directly coupled to input member 2I6 supporting clutch coils I26 and I40 therein, a power output shaft 2| 8, and intermediate quill shafts 220 and 222 telescoping one another and output shaft 2I8, supporting respectively at one end thereof drums 224 and 226 of the respective clutches I26 and I48.

Quill shaft 222 as provided near its free end with a pinion gear 228, having meshing engagement with a gear 230, said gear 230 having driving connection with a countershaft 232 through an overrunning clutch 234.

Countershaft 232 supports at opposite ends thereon gears 236 and 238, gear 236 having meshing engagement with a pinion gear 240 provided at the free end of shaft 220 whereas gear 238 meshes with a. gear 242 connected by way of overrunning clutch 244 to one end of shaft 2I8.

The shaft '2I8 is splined at 246 and by way of splines 2I2 of shiftable collar 206, forms, with splines or teeth 248, on the extremity of shaft 222, a crown or dental coupling 250. The splines 2 I2 of the collar 206 are adapted to interdigitate with the splines 248 on the shaft 222 upon shifting thereof to directly couple shafts 2I8 and 222 together for rotation in unison.

A' gear 252 connected to shaft 2 I8 through overrunning clutch 254 meshes with a gear 256 provided upon one end of a second countershaft 258. The counter-shaft 258 has intermediate its length splines or teeth 260 engageable with the splines of collar 204 axially shiftable thereon.

Gears 262 and 264 are journalled on the shaft 258 on opposite axially disposed sides of splines 260 and mesh respectively with pinion gears 228 and 240 of the shafts 222 and 220.

An annular member 266 lying adjacent the splined portion of shaft 258 and connected to shaft 258 by way of an overrunning clutch 268, is provided with external splines or teeth 210 having meshing engagement with splines 208 of shiftable collar 202.

The collar 202 is axially shiftable on splines 210 and together with external splines or teeth 212 on'thehub of gear 262 with which it is adapted to have engagement provides a crown or dental couayoommufli 1m 214; wh re the collar 203k axiallyrshiftablez on splines 260 is engageable with externalisplinesi orteethiflfion theihum of. gear Z624 tojformitherewith a crown: or dental. coupling 218.

I Reitrencaishadtoco-pendingaapplicationseri No. 864ml: for; a. more; detailed description: and. explanation: of: Operation, of: tr nsmission. I122 In; a normal: p -ration of transmissionza I" and control system; It therefor, with the ignitiom swit h; I lit, of; a. powen plant ior: propelling a. vethicle; of; which the; transmission I03 forms; a part, closed and the engine operating at idle speed the; system t2: will be at. virtual rest with; all of; the elements thereoftbesides switchu It in open! posit-- tionasshown by, Fig; 1.

With the; transmission placed; in; condition; for ransmitting: pow r thenethroushi such that fiwitich- III 4; is moved to" closedposition: innconducs ton ZZT-A and the, governor is, driven at; an: ample,- speed, from say output. shaft 2 18- of theitransmission to actuate; lever 3'0v thereof: to, have contact with switch; contact 34, an initial depression; of accelerator pedal I22 by way oft part1 I24 thereof: causes; engagement between: terminal; contacts: I06 and I I 2 providing for a flow of current by way" conductor 22-A-, conductor H14 through variable resistor III], conductor 22'-A, and branch conductor I38, for supply thereof to coil: I40:

through; closed switch I44. The, flow of current toiooil I40. through switch I44 is possible sinceitis thee-flow of' current) from battery I4 by way of QQnductOrZU, pigtail 28, lever 3!], switch, contact 34, conductor 46, and branch. conductor 48 to coil 5,6. operation. upon the energization thereof to actuate armature I52 and, close switch I44.

Thefiow of currentto coilr Moot, clutchv I42 is modulated'through the variableresistor I In con.- trolled" as by the vacuum of the, power plantacting upon diaphragm II8 againstthev spring resistance thereof. By so modulating, the flow: of current as controlled by engine, vacuum, a very smooth operation ofclutch I42 for startin gearoperation of'the vehicle is provided;

Fig; 2" illustrates schematically the flow of power through" the transmission for starting'gear wherein the power as transmittedfrom input shaft 2I4 by wayof clutch I42 flows-throughquill shaftizzz oonnected to-drum 'zzfi of the cliitcirby way of gear 228 thereof to gear 230 from gear" 230 tocountershaft 232 through over-running clutch connection therewith, thence through" countershaftna by way'of meshing gears z'iw and 242,: and; overrunning clutch. 2443 connection of ear- 242:. with output, shaft 2418ifor the output transmission of, power therefromx to the vehiclest wheels-t. I

As the speed of; the vehicle isiurther increased resulting; in; a movement; of the; lever" 3.0: thereof;

i i asi ned bytha peedoI theivehiclei delivered togovernor 32 thereof, the lever: 3:0: passes: from; switch contact 34 toswitch contact-36; setting; circuit 66. connected thereto into; operation. Simultaneously with the speed switch; change of; the: g vernor. the switch I I 1ii-n'iay bewactuatedto closed position I to bridge conductors 2,2A and, 22,A,, for;

the purpose of bye-passing-modulation cpntrolxof clutch; I zsthrough the elimination.ofgacoeleration control circuit I- 0 lat. this, time.

Upon changeover of the governor control from; switch contact. 34:, toswitc-h contact 36. a slight overlapis provided solthat a smoothtakeoveryin gear ratiot speed change, can; be effected. With thecircuit 64 supplied current, itv flows; through conductor 66 and branch conductor 12 resulting, iri energizing coil," of, solenoid"lfilthuseffecting;

Increment of; armature I3fs thereon and Mitch element: forming a; part? of: said: armature to: closer switch: to 8,: between; contact; terminals E3112- and; tilt permitting: of the: 110w oi: current: thereacrossi. Simultaneously with current flow circuit; 66; current is permitted to flow through conduction" Z2*A.,. across switch IiliG EQ-GOIld IIQt K lit-A and thence by was" or closed; switch. I28 to CD111 laces: Qlutclr. I:2;8ifo1; the: eneng-izatiom thereof-fl Eis; 3 illustrates; the condition; at 2nd ear: op eration wherein with: the: clutch P1423 desenere zudi and: clutch, I .28; encrgizedi, powenfiows; from input; shaft, 2 Mi, hroughzelutzchz 12% y w y-of its; drum 224; to 111111; sloiafizv Z-Ztg. thence to; countershattzlfii; by way 'ot. meshing engagement; between scared: and: 213. 1 from countershafrtxa 232.- by wawofi-meshi-t in engagement between gears; 2&8 and: 2425;. amt by; was? on overrunnmg clutch, 244's connected be tween, gear; 242 and; output, shaft" 2 I13 for dieliuemr therefrom.

h d: peed. ear: operationillustratetti in F s sai-ct acc tion: bei g: at a ned: as;- overnor. lever 30 moves; from; switch, contact 36; to; switch; contact I 33; therebydelivery currentv to conductor:

3 I81 resulting int supplying; currentzto-icoili 8,4 fioirthei operation, of; solenoid; as. Mcvementofi armature L 4,; of; the olenoid is; efiectedp by: its; energizatiom causing valve toil forming; a part thereof: toi be! moved in valve housing m6; therefor nesultingrim the delisseryofi air unden'p zessura; from a: suitable: o rc I n wn. rough: the: valve: housing; for delivery to air pressurecylinder If! As; aresultt oft the air under pressure being delivered; to: the: cylinder, the diaphragm I m thereof is actuated;

;; to) move l a shift rod: I84 connected"; theretow in: a

directionl to pivot. lever I95, and: alsoz 'toe move; switch? element, L9 It thereof, to switch OIDSEd'QQQSiw tion, Whereasthetpivoting; ofi lever lflfiaresultsdm the actuatiom of; collar of dental clutcht 254% to provide; coupling; engagement between annularg' member, 266;. and; hub. of: gear 262 wherein the; splines 21! 870i collar: 22'- engage-the splines 210,: and 212-. ot the, respective annular memben 2616; and; gear zsathe closing of switch 62: results int-cur rent: fiowv across; contact, terminals 60, and; p i thereof for delivery from I the. source thereof; for? energizationtofzcoilt 56 of solenoid. 58. With: the actuation of.-. armature I52-and switch; element. I 5!! connected thereto to. close-switche I44 and: with:

I thetnormally existent flow of currentinconduotorr 221; the. 0011 I40- ot clutch: I421 isssupplieda. current: resulting in the energization thereof. I

With, thezclutch- I142; energized-i and a gear, shift provided in the transmission, power willilflowrfrqnn shaft 214 through clutch. M2, thenceby- Way, of meshing engagement of, fiars 2-281 and-1:51 and, dental coupling of the hub off-gear; 252.. tolannular. member. through overrunningclutchl 263T to, count; tershaftflfitl; counterslraft '8"by way' ofgear 25E transmitting power to gear 252 which in turn; transmits it "through overrunni'ng clutch: 254"'con.-- nection with output shaft thereto for delivery theref'roma A furtherincrease in speed of the vehicle "will move the lever" arm or the governor to passi fromz'switch contacti38 toswiteh contact lll where -e upon". current, is: delivered; therethrough to acne duster: 8n; resulting" in: the: energization: of? coil 86-1 0t solenoid 9'2. With.thesolenoidienergizediarmae 1 tune; Iand valve element. I fiztzformingraz part 'ofz h armature; are: moved: whereby the: valve ole-- ment, Hi2 inlhousing; I68 operatesto perm-it: oft theiflow (if-air: pressure: throughtheqhousing; froms 31;,SQUICEF} notrshown to air pressure: cylinden k714i Ail'iQI'fiSS'LlI-B: delivered to cylinder I14; results; izu

7 overcoming the spring load imposed on the diaphragm I80 thereof such that the diaphrgam actuates shift rod I86 connected thereto to pivot lever I98 connected thereto and move switch element I92 to close switch 10 of which it forms a part.

The movement of lever I 98 results in the shifting of collar 204 of dental coupling 218 to couple the shaft 258 to the hub of gear 264 wherein the splines 2I0 of collar 204 engage with both splines 260 of shaft 258 and splines 216 on the hub of gear 264. Simultaneously with the movement of the collar 204 for a gear ratio change of the transmission the clutch I28 is energized as a result of the closing of switch 10 and the delivery of current from the source of power across terminals 98 and 68 of switch 10 to solenoid 16 for the actuation of armature I36 and switch element I34 to close the current flow circuit of conductor 22 to the coil I26 of clutch I28.

It is to be understood that as the governor lever 30 moves to complete current conducting relation with a different switch contact in either the staging up or down of transmission gear speed change, that the preceding stage of control returns to normal whereby the operational control thereof no longer exists aside from the overlapping provided in passin from one stage to the next. As a consequence in the case of lever 30 moving off switch contact 38 in passin to switch contact 40 provides for the elements controlled thereby to return to normal whereby the collar 202 is again shifted to uncouple annular member 266 from the gear 262.

Upon the energization of clutch I28 and shifting of collar 204 to couple shaft 258 to gear 264 a fourth speed of operation of the transmission is attained wherein as shown by Fig. power flows from input shaft 2I4 through clutch I28 and by way of drum 224 thereof to shaft 220, thence by way of meshing engagement between gears 240 and 264, and coupling of gear 264 and shaft 258 to gear- 256 connected to shaft 258, gear 256 in turn through meshing engagement with gear 252 coupled through overrunning clutch 254 to shaft 2I8 for the output delivery therefrom.

' With the movement of lever 30 of governor 32, as induced by higher speed of the vehicle, to bridge the switch contacts 40 and 42 and then pass completely to switch contact 40 a fifth gear speed ratio of operation of the transmission is attained.

Through engagement of lever 30 with contact switch 42 current flows therethrough to.conductor 82 for the subsequent energization of coil 88 of solenoid 94 resultin in the actuation of armature I58 and valve element E64 connected thereto. Valve element I64 is operatively movable in valve housing I effective to permit of the flow of air pressure from a source, not shown, to air pressure cylinder I16. As the air under pressure is delivered to cylinder I16 it operates to actuate diaphragm I82 against the resistance of the spring load imposed thereon, whereupon the diaphragm moves shift rod connected therewith. Shift rod I88 in its movement actuates pivoted lever 200 connected thereto and moves switch element I94 forming a part thereof engagement across contact terminals 52 and 96 to close switch 54. With switch 54 closed current is supplied thereacross and by way of conduit 46 to energize coil 56 of armature 50 effective upon the actuation of armature I52 of the solenoid to move switch element I50 to close the circuit for supply- 8 ing current to coi1 I40 of clutch I42 by way'of conductor 22. g

With clutch I42 energized and lever 200 pivoted to provide for engagement of dental coupling 250 wherein collar 206 is axially shifted to couple shifts 222 and 2I8 together for rotation in unison direct speed ratio is accomplished whereby the speed of shaft 2I4 aside from operating slip between the input member and drum 226 of clutch I42 is transmitted to the output shaft 2I8 by way of coupling relation between shafts 222 and 2 I3.

Simultaneously with the transmission operating completely in fifth gear, the fourth gear speed ratio is dispensed with as the lever 30 moves off of engagement with switch contact 40.

This completes an upstaging of transmission speeds from first or startin gear through fifth gear as controlled primarily by the action of governor 32 establishing the desired flow of current in circuit I6 as the output speed of the vehicle dictates. A downstaging of gear speed ratios will follow exactly in reverse the upstaging herein defined and it is not felt necessary to described same in view thereof.

The part of lever 30 engaging switch contacts 34, 36, 36, 40 and 42 is purposely made of a particular size so as to permit of a bridging of adjacent contacts in a downstaging as well as an upstaging of the transmission so as to provide for the selection of a higher gear when increasing speed and a lower gear with vehicle decreasing speed. As such when the vehicle reaches the normal running speed which provides the maximum horsepower at any given road speed, the lever will not bridge the space between the contacts and the gear previously used before the change is made, is then dropped.

While this invention has been described in connection with certain specific embodimentsthe principle involved is susceptible of numerous other applications that will readily occur to persons skilled in the art. The invention, therefore, is limited only as indicated by the scope of the appended claims.

What I claim is:

1. A control system for a prime mover driven transmission having a driven shaft, a plurality of power operated gear change mechanisms, a plurality of controlled elements including a pair of electromagnetic clutches, and a governor under the influence of the speed of the driven shaft; comprising an electrical power supplied network, an electrical circuit for controlling the operation of one of the clutches connected in the network including a set of normally open contacts, an electrical circuit for controlling the operation of the other clutch connected in the network including a set of normally open contacts, electrically operated switch means one for connecting the contacts of each clutch circuit, a plurality of electrical control circuits, one for each mechanism, means adapted to be actuated by governor for connectin the circuits for the mechanisms with the network and for connecting the switch means with the network and mans actuated by the mechanisms for connecting the switch means with the network.

' 2. A control system according to claim 1 wherein an ignition switch is provided in the network.

3. A control system according to claim 2 wherein the switch means are each arranged in separate circuits, said switch means having normally open contacts and being connected to the network at one end thereacross and at its other end with the network through the means associated with the governor.

4. A control system according to claim 2 wherein an acceleration control circuit is interposed in the circuit for one of the clutches, said circuit including a variable resistance controlled as by vacuum produced in the prime mover and normally open contacts adapted to be actuated by an accelerator for the prime mover to cause the current flow in the circuit topass through the resistance upon initial depression of the accelerator and upon full depression of the accelerator to by-pass the resistance.

5. A control system according to claim 4 Wherein the acceleration control circuit is interposed in the circuit for both clutches.

6. A control system according to claim 5 wherein switch means in the circuits for the clutches by-pass the acceleration control circuit.

7. A control system according to claim 2 wherein the governor includes a pivoted lever arm having current conducting means thereon connected in the network.

8. A control system according to claim '7 wherein the current conducting means are engageable with current conducting elements of the circuits for the mechanisms and the switches.

9. A control system according to claim 8 wherein the conducting elements are arranged in substantially arcuate spaced relation to one another.

10. A control system according to claim 3 wherein each mechanism includes a shiftable rod having a switch element as a part thereof engageable to close the contacts of the circuit of one of the switch means and adapted to have a gear speed change shift lever actuated thereby.

11. A control system according to claim 10 wherein the control circuit for the mechanism includes a solenoid actuated valve, said valve being movable in a valve housing for controlling the supply of air pressure for movement of the shifting rod of th mechanism.

12. A control system according to claim 8 wherein the current conducting means of the governor can bridge adjacent current conducting elements.

13. A control system according to claim 2 wherein there are three mechanisms and corrcspondingly three circuits and three current conducting elements therefor.

14. A control system according to claim 13 wherein the current conducting elements of the switch means and mechanisms provide in connection with the governor lever arm current conducting means five difierent gear speed controls for the transmission.

15. A control system according to claim 13 wherein the switch means for one clutch circuit is connected to the network by the means of two mechanisms and the switch means for the other clutch circuit is connected to the network by the means of the other mechanism.

16. A control system according to claim 15 wherein the one clutch circuit connected to the circuit by means of two of the mechanisms provides for operation of the clutch of said circuit in first, third and fifth gear speeds of operation of the-transmission and the other clutch circuit connected to the circuit by means of the other mechanism provides for operation of the clutch thereof in second and fourth gear speeds of operation of the transmission.

ANTHONY WINTHE-R. MARTIN P. WINTHER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 983,949 Sundh Feb. 14, 1911 2,244,092 Wheeler June 3, 1941 2,527,565 Miller Oct. 31, 1950 2,549,738 Winther Apr. 1'7, 1951 

